Effects Of Ricinus Communis Linneaus (euphorbiaceae) Extracts On Leishmania Major Promastigotes And On Infected Balb/c Mice
Abstract
The effect of castor oil plant seed oil fractionally extracted with diethyl-ether
and the aqueous extracts of its leaves was tested in vitro on Leishmania major
(Yorkimov and Schokor, 1913) promastigotes and in vivo on Leishmania major
lesions in inbred BALB/c mice. Four experimental groups of 35 female mice
each were used namely seed oil group (oil topically applied); Aqueous leaf
extract group (extract administered intraperitoneally); Pentostam'P (sodium
stiboglnconate) group (drug administered intraperitoneally) and a control group
(untreated infected mice). Before infection, footpad measurements were taken
by measuring the left hind footpad (LHFD) and _the contralateral right hind
footpad (RHFD). All the mice were infected intradermally with L. major
stationary primary phase metacyclic promastigotes at a dosage of 1 x 106 per
10111on the left hind footpad of every mouse and lesion sizes measured weekly
at 7 day intervals. Treatment was commenced 30 days post-infection. Within
this time lesion sizes were-measured using vanier calipers every 7 days. The
experimental groups were treated for six weeks and observed for another 2
weeks before being sacrificed. Impression smears and cultures of spleen were
made to determine the parasite load and visceralization while right hind
,
footpad, (RHFD), was left as a contralateral control. Results of the study
showed that there was antileishmanial effect due to the R. communis oil that
was significantly better than theeffect of the leaf extracts (Tukey test, q=4.059,
P<0.05). However, the effect compared poorly to the standard treatment drug.
Notwithstanding, it was found that the R. communis aqueous leaf extracts was
much better at preventing metastasis, visceralization, and a much lower
Leishmania donovani Unit (LDU) than the seed oil possibly due to the that the
leaf infusion was administered intraperitoneally. Surprisingly enough the seed
oil appeared to have visible effects at reducing lesion size that was significantly
better than the leaf extract. However sodium stibogluconate still proved better.
It is recommeded that R. communis seed oil be explored further as a potential
canditate for use in combination therapy with other antileishmanial drugs used
for the treatment of cutaneous leishmaniases.
Citation
Masters of Science in ZoologyPublisher
University of Nairobi